Fundamental constraints for the length of the MOSFET conduction channel based on the realistic form of the potential barrier

TL;DR

This paper revises the minimum channel length constraints for silicon MOSFETs by considering the realistic potential barrier shape, revealing that quantum tunneling effects impose fundamental limits near 1.2 nm, explaining the practical scaling barriers.

Contribution

It introduces a more accurate estimation of the minimum MOSFET channel length by accounting for the true potential barrier shape, challenging previous simplified models.

Findings

Quantum tunneling shortens effective channel length

Minimum channel length estimate is around 1.2 nm

Scaling limits of silicon MOSFETs are nearly reached

Abstract

The work estimates the minimum channel length of the MOSFET transistor, which is the bacis device of modern electronics. Taking into account the real shape of potential barrier in the channel shows that the electron tunnels through a region significantly shorter than the physical length of the channel in the presence of drain voltage, and so the available estimate of the minimum quantum constraint channel length in silicon MOSFET, 1.2 nm, is significantly underestimated. The fact makes it clear why after reaching 5 nm working lengths of the channel it was impossible to reach the long-declared values of 3 nm under maintaining the proper level of functionality of the transistor. The estimates made in this work confirm that the fundamental scaling limits of silicon MOSFETs have almost been reached.